I did the X80 the same way I measure all the lights. Bare LEDs are the exception. They are as floody as can be, so with those I don’t use the diffuser since I have to get the whole dome inside the sphere and the light is pretty much perfectly diffused as it is. And a bare LED can’t really be pushed against anything.
Texas_Ace BLF Calibrated Lumen tube / Sphere No math skills needed - Several spheres still available
If your integrator (box, tube, whatever) is properly designed and is doing its job you shouldn’t have to adjust anything to account for beam shape. That’s the whole point of the integrator - that’s its job. That’s assuming a flashlight shined through a hole though, I can see how a bare LED would be an exception since its probably measured more like a light bulb. Bare bulbs are mounted right in the center of the sphere for testing, not shined through the side right?
Omnidirectional 4pi steradian (or thereabout, rarely do they radiate as much below because of the fitting) bulbs in the center yes. 180° (2pi steradian, hemisphere) LEDs from the side.
Ya’ know, while this is all quite interesting; I think it needs to be in a thread of it’s own doesn’t it. This thread is about the Texas_Ace BLF Calibrated Lumen tube, not the TUNING Tube. They are two different creations.
We should be comparing data & results of our TA Tubes here.
Just a thought………
(the light hitting a baffle has hardly any influence on the reading of a proper sphere)
I think it is time that you read into integrating sphere design and find out how all your concerns can be adressed in a well designed device. A good read that does require some attention is this: https://www.google.nl/url?sa=t&source=web&rct=j&url=https://www.labsphere.com/site/assets/files/2551/integrating_sphere_theory_apps_tech_guide.pdf&ved=2ahUKEwjdnMrB4OfcAhUQYVAKHVjUDp8QFjAEegQICRAB&usg=AOvVaw1upnU1ZSSWAdwaTbWF7G6-
It would save a lot of words in this thread.
+1——Was my thinking exactly—Considering all the water that been passed under this bridge
Yes please
After reading Integrating Sphere Theory, an idea occurred to me that is not in that document, and that is a triple adjacent sphere design, with the photo sensor in the third sphere. Like this. The two smaller spheres should be side by side rather than stacked but thats harder to illustrate in 2D. I guess it still doesn’t preclude the need for a baffle does it….
Thanks for posting the link to Integrating Sphere…Theory and Applications djozz.
Good info & interesting read! 
………
Interesting idea Hoop…. very interesting.
I’m not sure if adding even a second diffuser would add any extra integration. I used the design with satellite small sphere in one of my spheres. Apart from extra integration it is very good for lowering the reading of the luxmeter so that the measuring range is increased (for a single sphere to measure over 10K lumen without using grey filters over the sensor, a sphere larger than 40cm is needed, for 20K lumen almost 60cm)
I’m having to ditch the inlet diffuser as no system on earth can possibly work universally by utilising one. My Cometa and M43 have heads that are far too dark. On both the TA tube and mine the Cometa can’t pass 300 Lumens (TA also tested his Cometa at under 300) a ceiling bounce or ditching the diffuser sees the Cometa triple it’s output when compared to a light with a tight beam.
Every Flashlight has different self absorbing rates from light reflecting back. I’ve also yet to see a diagram of a sphere that would measure both an Aspheric light and 30000 lumen 180 degree X80-GT accurately. The Cometa would put a dot on the sphere wall, the X80-GT will either put high levels of spill directly into the sensor or it’ll fire a considerable amount of spill at the baffle. Even if this added absorption is only 5% that’s 1500 lumens off the reading.
I think these 2 lights would have to be in the middle of a large sphere firing straight up with the sensor at the bottom of the sphere, hard to replicate at home.
I’m gonna remove the futile entry diffuser from my lightbox and move the sensor until all 30+lights are within an acceptable tolerance range.
KG_T I can hardly believe that you spend so much effort in raising multiple and specific objections to the various light measuring devices, plus altering your own device multiple times, without even taking the trouble to read yourself into the subject, which would take away every objection you have, would help building your machine in a proper way, and would stop you polluting BLF with what I see as uninformed junk.
(and yes there is a very effective and simple solution to compensate for the specific reflectivity of the light source, which is called an auxilliary light, which I use in my various spheres. But in your typical way of not responding to help and just repeating yourself you are not likely to read into that either)
I want to get around using any form of compensation.
I’ve got the sensor facing the roof at entry point away from any spill advantage and it’s just a case of getting the right amount of diffusion before the sensor as the lights are now reading higher.
My D4 XP-L HI is reading 4,000, the BLF X5 Kronos 1,300, Acebeam EC50 Gen II 2600, so nearly there but the X80-GT is still reading 36,000, a little bit of spill is just hitting the roof above it so I’m gonna reluctantly use a mirrored ledge just to control it. (unavoidable sadly)
I can aim a thrower all over the box and the reading doesn’t change!!! YEEEEEESSSSSSSSS!!!
I haven’t really been following this thread, but it’s a rare moment to see djozz indicate anything but the utmost respect for others… so I’m guessing things went pretty far off the rails.
What would get this thread back on track?
Edit: Actually, that’s probably the wrong question. It sounds like the TA tubes and KG tubes probably just need to be in different threads. They’ve diverged far enough to be totally different projects. Time to start a new thread?
I’ve slightly changed the attack angle of the input to angle acute spill from the roof above the sensor and the X80-GT is at 29000 lumens, same as when I ceiling bounced it versus the floody X80/DX80/X45/Frosted D4 calibrated to their average review scores. 23k/30k/15k/3k
Thanks for the input guys. I do want to present perfect flashlight reviews and sometimes that means looking for flaws in everything.
Now to pester the CRI guys….
You still think you need a properly measured light source to get a calibration. Right now your just giving it your best guess like all other previous home made lumen tubes and spheres.
Congratulations, you’ve built a device that tells you what you want to hear instead of what you need to hear. Flawless…
KG_Tuning….
1. You were asked yesterday by several people, and asked nicely I might add; to start a new thread about your device. This was to end your hijacking of this TA LUMEN TUBE thread. It has been ‘suggested’ to you again today. Will you please follow that suggestion.
It appears you are the only one not happy with & having problems with the TA TUBE…… Does this not suggest to you that the problem is not with the TA TUBE, but instead with you & your use of the tube??
If if doesn’t… it should.
2. It appears all you are doing is trying to make your device make the numbers you ’think’ your lights should produce.
Do you still not realize that unless you calibrate your device with a known calibrated light source(such as maukka’s calibration lights to name one)_ your lumen numbers mean absolutely nothing in the realm of reality??_
You have been told this by people who know what they are talking about. Yet you refuse to listen & ramble on aimlessly.
Why??
Start from the solution and work backwards - the anti-scientific method
I’m extremely happy with it, my Nitecore Tube reads 45 lumens and my DX80 30,000 lumens.
On the Texas_Ace tube the Nitecore Tube didn’t register and my DX80 reads 20,000
My 6500k Convoy S2+ which to date I’ve seen Maukka send out 268-282 variants reads in that bracket!
The Cometa still reads under 300 Lumens though. Guess I’ve just got to deal with that. Tbh the TA tube isn’t far off, it just struggles with high power flooders. We could easily back that up by putting a calibrated X80 in it instead of a S2+ on mid mode.
You can’t use 1 light to make a system, I could fire a S2+ at a lux meter from 10m away and get a 270 lux reading to qualify as “270 lumens” to match Maukka’s calibration figure, now what does that meter read when a MF04 is fired at it from the same distance? Between the expected 1800-2400?… Hell no. You need all kinds of beams to calibrate a system and that’s what I’ve done.